Motor-controller.



No. 850.443. PATENTED APR. 16, 1907. A. PEDBRSEN.

MOTOR CONTROLLER. APPLICATION FILED AUG. 1a, 1905.

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A. PEDERSEN. MOTOR CONTROLLER. APPLICATION FILED AUG. 16. 1905.

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UNITED STATES PATENT OFFICE.

' ADOLPH PEDERSEN, OF CLEVELAND, OHIO, ASSIGNOR TO THE VAN DORN- ELLIOTT ELECTRIC COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO MOTOR-CONTROLLER.

Specification of Letters Patent.

Patented April 16, 1907.

Application filed August 16. 190 Serial 7 3 Cleveland, county of Cuyahoga, and State of Ohio, have invented a new and useful Improvement in Motor-Controllers, of which the following is a specification, the principle of the invention being herein explained and the best mode in which I have contemplated applying that principle so as to distinguish it from other inventions. I

My invention relates to motor-controllers and its object is to supply such a device that shall be especially adapted for use upon small motors, such as are employed in portable electrical drills and analogous machines.

Said invention consists of means hereinafter fully described, and specifically set forth in the claims.

The annexed drawings and the following description set forth in detail certain mechanism embodying the invention, such disclosed means constituting but one of various mechanical forms in which the principle of the invention may be used.

In said annexed drawings, Figure 1. represents a horizontal section of my improved motor-controller, taken upon the plane designated bythe line 1 1, Figs. 2, 3, and 4.

Fig. 2 represents a vertical section thereof, taken upon the plane indicated by the line 2 2, Figs. 1 and 3, in combination with a portion of the casing of a portable drill and the field structure of a multipolar series-wound constant-potential electric motor. 1g. 3 represents a vertical section taken upon the plane designated by the line 3 3 Figs. 1 and 2. Fig. t represents a vertical section taken upon the plane designated by the line 4 4, Fig. 1; and Fig. 5 is adiagram illustrating the circuit and connections.

My invention is designed to be an improvement upon the motor-controller set forth in my pending applicatiorifor United States Letters Patent, Serial No. 262,368, filed May 26, 1905, the modifications and changes from the structure there disclosed being made with the purpose of producing an equally-efficient controller that shall be adapted for use on lighter machines. Thus the motor controller described in the above application is found to be unduly cumbersome when applied to drills weighing less than thirty pounds, whereas the device shown in this ap-v plication is constructed so simply and of such light material as to be capable of being affixed to a machine weighing from five to thirty pounds without adding perceptibly either to its weight or compass, and at the same time its control is equally effective in its operation. Said invention is adapted for use in a great many situations; but it is especially serviceable as applied to electrical drills. Accordingly I have shown it in the drawings in combination with a portable electricallydriven drill and shall now describe its construction and operation in such connection;

Upon the motor-frame M is mounted a casing A, within which the controller is incased, so that it is entirely outside the reach of the operator and cannot be tampered with either through ignorance or malice. Projecting within such controller-casing A andjournaled in a block N is the inner end of an operating handle NJ 'Rotatably mounted upon this inner end of handle N, but insulated there from, as clearly shown in Fig. 4, are two independent contact members or switchblades H and. I. These blades, while movable independently of each other, are nevertheless in contact with each other so as to form a continuous conductor.

Suitably insulated from the motor-frame M, upon which they are supported, are two contact-springs K and L, adapted to contact with switch-blades II and I, respectively, when they are positioned as shown in Fig' 1. Normally these blades are held in their off position intermediate of the contact-springs K and L by means of a helical spring S, which encircles the block N and is secured at one end to blade H and at the other to blade I. To retain switch-blade H in its on pcsition."i. 6., in contact with spring Kan electrically-controlled device is provided. This device comprises, primarily, a solenoid B in circuit with the motor to be controlled and which, as shown, is mounted within the drillcasing, but which in other connections would I is pivoted upon a support F by means of a 1 pin F, such support being mounted upon the I motor-frame M. The pivotal movement of j lever E is restricted by afair-leader G, likei wise mounted upon frame M. Normally plunger B is held withdrawn from solenoid B as far as fair-leader G will permit by means of a helical spring E, attached to the other end. When lever Eis in this position, a pin 6 on its upper surface engages switch-blade H in the manner shown in Fig. 5, and so holds it in its on position. It is evident from the description of this retaining device that upon the character of the current becoming such as to cause solenoid B to attract plunger B with sufficient force to overcome spring E switchblade II will be released and under the influence of spring S will assume its normal off position. To similarly retain switchblade I in its on position, a catch T, Figs. 1 and 5, is provided, being held in proper position to engage a lug t on the upper surface of blade I by means of a pin 25 and coil-spring ii. To release switch-blade I, and thus allow it to assume its off position, a pointer P is rotatively attached to the inner end of handle N, being so shaped as in the course of its rotation to disengage catch T from pin it. This pointer is further utilized to return such switch blades H and I to their on positions. To this end switch-blade I is provided with two laterally-extending ears I and I from Which project upwardly lugs I and 1", respectively. I/Vhen blade I is in its off position, it may accordingly be re turned 'to its on position by swinging pointer P around until it engages lug I whereupon by further rotation in the same direction the blade I will be brought into engagement with catch T. Similarly when blades H and I are both in their off positions if pointer P be swung in the opposite direction it will engage lug I and upon further rotation a lug I projecting downwardly from blade I, which lies over blade H, will engage blade H and carry it into engagement with lug e on lever E. To-facilitate such engagement, the portion of blade H which is thus brought in contact with lug e is beveled on its under surface, as shown at e, Figs. 1 and 5. The sides of the controller-casing and the lug I prevent the switch-blades H and I from being pulled by the spring S beyond their central 0H position. 7

From the diagram shown in Fig. 5 the curcuit can be traced very readily, as follows: from the connecting-cable through the positive terminal to the contact spring K, switch-blade H, switch-blade I, contactspring L, solenoid B, field-coils M, the com mut-ator and negative terminal and thence out.

The operation of my controller is as follows: During the ordinary operation the switch-blade I is utilized, said blade being thrown to its off position by means of the turning pointer P, which is manually operated to the left to engage the catch T and release the pin t therefrom, whereupon the switch-blade I is actuated to its ofl' position by means of the spring S, this movement of the switch-blade I ahead of and independent of the pointer P resulting in the securing of a very quicleacting brake. The turning of the pointer P to the right will cause'the same to engage with the pin 1*, thus turning the switclr-blade I so as to contact with the spring-contact L and at the same time per mit the pin t to be engagedby catch T, the switch-blade H in the meanwhile remaining in its on position. Under excessive load the circuit is broken by means of the switchblade H, said blade being thrown to its off position by means of the spring S when the flux of the solenoid reaches a quantity great enough to draw the plunger B into the solenoid B, and thus release the switch-blade II from the pin e upon the lever E. The solenoid is previously adjusted so the amount of flux required to produce the above-described effect is less than the quantity that has been found dangerous to the operation and safety of the machine. The manner in which the switch-blade H is returned to its on position by means of the operating-pointer P has already been indicated, as has also the manner in which blade I is returned to its on posi tion. l

It will be noted from the above description and the accompanying drawings that the safety feattre of my device is wholly automatic; that the starting and stopping are wholly controlled throrgh the switch-blade I except when the magnetic fiuX of the motor becomes excessive, when the break is occasioned by the throwing of the switch-blade II to its off position, and, further, that the reestablishrnent of the contact between the switch-blade H and spring-contact K cannot be effected without first throwing the contactblade I out of contact with the springcon-' tact IJ.

In addition to differences from the device shown in the aforementioned application that are readily apparent upon a perusal of the foregoing description I desire to call attention to the fact that in this device the action of the solenoid is not assisted by the magnetic flux of the field, but is energized entirely by the strength which it derives from the current, whereas in my former application the solenoid has been shown as secured to the back of one ofthe field-magnets, and hence has been assisted in its attraction of the plunger B by the magnetic flux of such field-magnet.

This invention comprises a motor-controller of a very small type, and it would be inconvenient, if not absolutely im ossible, to locate the solenoid within the sp ere of the field created by the motor.

The form of construction herein shown renders my device very exact and effective, inasmuch as any desired size and strength of solenoid may be used, and the quantity of flux that will be enerated in the same can be accurately calcu ated for any given current. It will be further noted that I have provided a very convenient arrangement whereby one of the handles utilized for moving and guiding the drill or other machine is also utilized for operating the controller, although obviously separate handles might be used for these two purposes; that the operative can in no way hold or force the machne to the work over and above its adjusted capacity; that my improved motor-controller is, in effect, a simple safety-switch, and that it is very reliable, cheaply constructed, and readil'y'applicable in any circuit as a substitute for a in se.

Having thus described my invention in detail, that which I particularly point out and distinctly claim is- 1. In motor-controllers, the combination of a movable contact member; means for actuating the same; a second contact member mechanically retained in its on position; and manually operable means adapted to release said second member from such mechanical retention whereupon the circuit is automatically opened, said latter means being also adapted to actuate said second member to its on position.

2. In motor-controllers, the combination of a movable contact member; means for actuating thesame; a second contact member mechanically retained in its on position;

and manually-operable means adapted to release said second member from such mechanical retention whererpon the circuit is automatically opened, said latter means being also adapted to actii ate both of said contact members to their on position, respectively.

3. In motor-controllers, the combination of a movable contact member; means adapted to hold the same normally in'a predetermined osition; a second contact member mechanically retained in its on position; and manually-o erable means adapted to release said secon member from s1: ch mechanical retention whereupon the circuit is automatically o ened, said latter means being also adapte to actuate said second member to its on position and said first member to positions other than said predetermined position.

4. In motor-controllers, the combination of a movable contact member; means adapted to hold the same normally in its off position: a second contact member mechanically retained in its on position; and manually-operable means adapted to release said second member from such mechanical retention whereu pon the circuit is an tomatically opened, said latter means being also adapted to act; ate both of said members to their on positions, respectively.

5. In motor-controllers, the combination of a movable contact member; means adapted to hold the latter normally in its off position; a second movable contact member mechanically retained in its on position and adapted to move'said first member to its on position; and a handle adapted to control the movements of. said second member.

and to release the same from said mechanical retention.

6. In motor-controllers, the combination I of a movable contact member; a second movable contact member mechanically retained in its on position and adapted to move said first member to its on position; means adapted to hold both of said contact memhers normally in their off positions; and a handle adapted to control the movements of said second contact memberand to release the same from said mechanical retention.

7 In motor-controllers, the combination of two movable contact members, one of said members being electrically operated to break the circuit when a certain electrical condition therein is attained, and the other of said members being only manually operable to control the stopping and starting in normal operations; means tending to throw both of said members into their 0 position; means adapted to effect such manual operation, such latter means adapted to move said first member to its on position; and means adapted to efiect such electrical operation.

' 8. In motor-controllers, the -combination of two independently-movable contact members in series, one of said members being electrically operated to break the circuit when a certain electrical condition therein is attained, and the other of said members being only manually operable to control the stopping and starting in normal operations; means'adapted to effect such electrical operation; and'means adapted to effect such manual operation, the movement of said first member to its on pos tion, after said electrical operation, being effected by said last-named means and resulting in the move- IOO of a movable handle; a pointer fixed thereon;

two switches rotatable thereon; a solenoid in the motor-circuit, means connected with the core of the latter and adapted to retain one switch in its on position Whensaid core is in its outermost position and to release the same upon the inward stroke of said core; a

v provided with means adapted to retain one switch in its on position when said core is in its outermost position, a predetermined flux in the solenoid-field adapted to effect the inward stroke of its core whereby said switch is released; a catch adapted to retain the other switch in its on position, said pointer adapted to disengage said switch from said catch; a retractile spring tending to throw both switches to their 'ol f positions; a lug upon said second'switch adapted to engage and move said first switch; and lugs upon said second switch adapted to be engaged by said pbinter.

11. In motor-controllers, the combination of two switches; manually-operable means for actuating one of said switches, said switch having a movement independent of said actuating means, the other of said switches adapted to be moved to its on position when said first switch is moved to its off position.

12. In motor-controllers, the combination of two switches; manually-operable means for actuating one of said switches, said switch having a movement independent of said actuating means; electrically-controlled means for operatin the other switch to its off position; an means for actuating said latter switch to its on position.

13. In motor-controllers, the combination of two switches; manually-operable means for actuating one of said switches, said switch having a movement independent of said actuating means; and electrically-controlled means for operating the other switch to its oii position, the actuation of said first switch to its off position effecting the ac tuation of the second switch to its on position.

14. In motor-controllers, the combination of two switches; manually-operable means for actuating one of said switches, said switch having a movement independent of said actuating means electrically-controlled means tending to operate the other switch to its off position; and means for actuating said latter switch to its on position.

15. In motor-controllers, the combination of two switches; manually-operable means for actuating one of said switches, said switch having a movement independent of said actuating means; and electrically-controlled Ineans tending to operate the other switch to its off" position, the actuation of said first switch to its oil position effecting the actuation of the second switch to its on position.

16. In motor-controllers, the combination of two switches; manually-operable means for actuating one of said switches, said switch having a movement independent of said actuating means, the other switch being actuated to its off position only by means of a predetermined current; means controlled by said current for so actuating said second switch to its ofi 't position; and means for, actuating said latter switch to its on position.

17. In motor-controllers, the combination of two switches; manually-operable means for actuating one of said switches, said switch having a movement independent of said actuating means, the other switch being actuated to its off position only by means of a predetermined current; means con trolled by said current for so actuating said second switch to its oil position, the actuation of said first switch to its ofi' position eflecting the actuation of the second switch to its on position.

18. In devices of the general character described, the combination of the motor and a suitable casing therefor; a controller supported upon said casing and comprising two movableswitches; manually-operable means adapted to control the DOVGZTBIHZS of one of said switches; and a solenoid mounted in said casing and adapted to control the move ments of the other switch.

19. In devices of the general character described, the combination of the motor and a suitable casing therefor; a controller supported upon said casing and comprising two adapted to control the movements of one of said switches for normal operations of the tool; and a solenoid mounted in said casing and adapted to control the movements of the other switch so as to enable the sarne to open the circuit'when a predetermined electrical condition is reached therein.

20. In devices of the general character described, the combination of the motor and a suitable casing thereforya controller-casing mounted upon said motor-casing; a handle for moving and guiding the tool; a pointer fixed to said handle; circuit-breaking means within said controller-casing, said pointer adapted to control the movements of said circuit-breaking means for normal operations; and a solenoid adapted to control the movements of said means so as to enable the same i to open the circuit when a predetermined l electrical condition is reached therein.

, 21. In devices of the general character demovable switches; manually-operable means scribed, the combination of the motor and a 1 scribed, the combination of a motor and a suitable casing therefor; a controller-casing mounted upon said motor-casin a handle for moving and guiding the too extending exteriorly from within said controller-casingf a pointer fixed to said handle within said controllercasing; circuit-breaking means tend ing to hold the circuit open, said pointer adapted to control the movements of said 1 circuit-breaking means for normal operations of the tool; and a solenoid mounted in the 1 motor-casing and adapted to control the movements of said circuit-breaking means so i as to enable the same to open the circuit 1 when a predetermined electrical condition is l reached therein.

22. In devices of the general character desuitable casing therefor; a controller-casing mountedupon said m0tor-cas1ng,'a handle for moving and guiding the tool and extending exteriorly from within said controller-casing; a pointer fixed to said handle within said controller-casing; two movable switches, said pointer adapted to control the movements of one of said switches for normal operations of the tool; and a solenoid adapted to control the movements of the other switch so as to enable the same to open the circuit when a predetermined electrical condition is reached therein.

Signed by me this 7th day of August, 1905.

ADOLPH PEDERSEN.

Attest:

JNo. F. OBERLIN,- G. W. SAYwELL. 

